Milling method and use of a cutting insert

Abstract

A method for milling a workpiece by way of at least one substantially polygonal cutting insert, which is arranged in a tool holder. A spindle axis of the tool holder encloses an angle of more than 0° with a plane normal to a machined workpiece surface. An effective lead angle between a main cutting edge of the cutting insert and the machined workpiece surface lies between 0° and 20°.

The invention claimed is: 
     
       1. A method for milling a turbine blade, the method comprising:
 providing at least one substantially polygonal cutting insert arranged in a tool holder, the tool holder having a spindle axis and the cutting insert having a main cutting edge, the at least one cutting insert is a substantially triangular indexable cutting insert or a substantially quadrangular indexable cutting insert or a substantially pentagonal indexable cutting insert, with the cutting insert inserted in the tool holder with a theoretical lead angle between a normal to the spindle axis and the main cutting edge of the cutting insert to between 20° and 40°; 
 milling the turbine blade with the cutting insert held in the tool holder with a feed, simultaneous to a rotation of the tool holder about the spindle axis, in a feed direction oblique to the spindle axis of the tool holder and transverse to a plane normal of a machined turbine blade surface, and thereby: 
 inclining the spindle axis for setting the spindle axis of the tool holder to enclose an angle of between 3° and 35° with a surface normal of the machined turbine blade surface and for setting an effective lead angle between a main cutting edge of the cutting insert and the machined turbine blade surface to lie between 5° and 20°. 
 
     
     
       2. The method according to  claim 1 , which comprises setting an axial cutting depth to less than 3.0 mm. 
     
     
       3. The method according to  claim 1 , which comprises setting a feed per tooth between 0.60 and 0.90 mm.